High ksoftirqd/1 cpu usage with openvpn

[dedicatedorange]

Hi,
Using openvpn on an aws instance using Amazon Linux 2. When a client connects and tries to transfer a file (from a file on another server), it goes quite slow and on the instance the cpu usage is almost entirely used (99%) by ksoftirqd/1 for the duration of the transfer.

Is there any pointers to troubleshoot this, I can find very little in relation to ksoftirqd/1 in relation to openvpn, has anyone else seen this?

[TinCanTech]

A quick search for ksoftirqd using duckduckgo gives plenty of results about CPU usage.